Clamping devices for retaining pipes, tubing and hose carrying hydraulic oil, air, coolant or other fluids in fixed position are popularly employed in numerous industrial applications. For instance, one such common clamping application involves the clamping of assemblies supporting two or more tube fittings or hose connections, such as those encountered in heat exchanger systems, hydraulic systems, and the like. One such clamping assembly is the MULTI-CLAMP.TM. clamping system, manufactured by Hydro-Craft, Inc., of Rochester Hills, Mich. Generally speaking, this system includes a clamping assembly adapted to hold a plurality of fittings for hose or hydraulic connections which may be of the same or of different sizes. Various features of the MULTI-CLAMP.TM. system are disclosed in U.S. Pat. Nos. 3,397,431 and 3,414,220 of William R. Walker.
A clamp device such as the MULTI-CLAMP.TM. assembly can be secured to a surface by welding a weld adapter to the surface and fastening the U-shaped channels of the clamping device to a bolt associated with and rigidly held in place in the weld adapter. A weld adapter, as used herein, is a generally rectangular block of metal adapted for receiving and holding in a stationary position a conventional fastener, such as a bolt, by its head end. The weld adapter is of sufficient mass so that it can be readily tack welded with a conventional arc or gas welder to a mounting surface so that the fastener projects away from such surface. The mounting surface could be any rigid metal member, from the frame of a machine or vehicle to a structural steel beam in a factory. A clamp can then be fastened to the fastener of the weld adapter, which protrudes from a face of the rectangular section. Weld nut adapters must be fairly thick in order to be sufficiently strong and rugged to stand up to heavy welding and the kinds of loads which may be placed on the fasteners held therein.
Until the present invention, the most efficient way known to make weld adapters has been to fabricate them by hot forging methods. Unfortunately, hot forging methods tend to be economically undesirable for making weld adapters. In particular, hot forging methods typically require an induction furnace (requiring increased energy consumption), special handling equipment, and special equipment to control pollution that is attendant with hot forging methods. Accordingly, the production of smaller quantities of (i.e., less than 100,000) of hot forged weld adapters in a single run is generally economically impractical.
Accordingly, it is an object of the present invention to provide a method of making weld adapters that does not incorporate hot-forming methods.
It is a further object of the present invention to provide a method of cold stamping weld adapters from relatively thick metal stock using progressive stamping techniques to produce reliably and economically small lots of weld adapters suitable for being tack welded to a support surface.
It is a further object of the present invention to provide a novel progressive die set for use in a knuckle joint press for stamping weld adapters.